1. Field of Invention
The present invention relates to a biochip structure, and particularly to a biochip with a plurality of microchannels.
2. Description of the Related Art
The cell is the fundamental unit of living organisms and has a sophisticated structure with complex biochemical reactions, which make artificial imitating or cloning a cell almost impossible. The cell plays a very important role in pharmacy developments. Due to the interaction between the medicament and the cell and the subsequent series of changes in cell morphology and cellular metabolism, it is able to speculate the functionary mechanism of a medicament and to evaluate activity and toxicity of a medicament through experiments of a medicament on cells. Due to the complexity of a human body system, the influences of applying certain medicaments on a human body are normally first experimented in a cell-level. The cells used for experiments provide many advantages, such as reaction-directness, high susceptivity and observation convenience and researchers can usually deduct a possible functionary mechanism of the medicament in the human body from the cellular responses. In this regard, it is useful for the pharmacy industry today to use incubated cells for researches and developments of target medicaments.
The benefits of miniaturization on biochemical experiments include quantitative accuracy, smaller amounts of samples, single observation for diverse reactions and easy automation. Since the miniaturization technique has been full-grown today, many traditional incubators are gradually replaced by minimized biochips, where cells are incubated in the biochip with microchannels for evaluating the actions of the medicament in the specific kind of cells. Generally, the cells are incubated in the microchannels of the biochip and a liquid containing a testing medicament is injected to the microchannels. During the flow of the liquid, the medicament reacts with the cells. Hence, by observing the cells afterward, the stimulating or action mechanism of the medicament on the cells are evaluated. To prevent the testing medicament from being diffused the microchannels and eliminate possible adverse influences in the reaction time of the testing medicament, the medicament is usually enfolded by bubbles first and then transported. In this way, the desired action time of the medicament on the cells are precisely controlled.
The key problem of the biochip with microchannels is how to enable the liquid therein to move simultaneously at a plurality of microchannels. Although the conventional biochip with microchannels use a flow-sharing scheme (so-called stepwise model) for the liquid flow that the geometric changes encountered during liquid's filling in the microchannels allows the liquid at different microchannels to await for each other. However, the liquid does not pass through each channel at the same time, and the goal of simultaneously observing all the microchannels for processing is unfeasible. Another solution with the prior art is to provide a biochip assembled by laminar plates and porous membrane valves, which is not suitable for the disposable design due to the expensive costs thereof.